Commit Graph

89 Commits

Author SHA1 Message Date
Amir Goldstein
4f911138c8 fs: add generic helper for filling statx attribute flags
The immutable and append-only properties on an inode are published on
the inode's i_flags and enforced by the VFS.

Create a helper to fill the corresponding STATX_ATTR_ flags in the kstat
structure from the inode's i_flags.

Only orange was converted to use this helper.
Other filesystems could use it in the future.

Suggested-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-08-17 11:47:43 +02:00
Theodore Ts'o
5afa7e8b70 fs: fix reporting supported extra file attributes for statx()
statx(2) notes that any attribute that is not indicated as supported
by stx_attributes_mask has no usable value.  Commits 801e523796
("fs: move generic stat response attr handling to vfs_getattr_nosec")
and 712b2698e4 ("fs/stat: Define DAX statx attribute") sets
STATX_ATTR_AUTOMOUNT and STATX_ATTR_DAX, respectively, without setting
stx_attributes_mask, which can cause xfstests generic/532 to fail.

Fix this in the same way as commit 1b9598c8fb ("xfs: fix reporting
supported extra file attributes for statx()")

Fixes: 801e523796 ("fs: move generic stat response attr handling to vfs_getattr_nosec")
Fixes: 712b2698e4 ("fs/stat: Define DAX statx attribute")
Cc: stable@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-04-17 23:03:50 -04:00
Christian Brauner
549c729771 fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner
0d56a4518d stat: handle idmapped mounts
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christoph Hellwig
f2d077ff1b fs: remove KSTAT_QUERY_FLAGS
KSTAT_QUERY_FLAGS expands to AT_STATX_SYNC_TYPE, which itself already
is a mask.  Remove the double name, especially given that the prefix
is a little confusing vs the normal AT_* flags.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-26 22:55:05 -04:00
Christoph Hellwig
b3f0515004 fs: remove vfs_stat_set_lookup_flags
The function really obsfucates checking for valid flags and setting the
lookup flags.  The fact that it returns -EINVAL through and unsigned
return value, which is then used as boolean really doesn't help either.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-26 22:55:05 -04:00
Christoph Hellwig
09f1bde401 fs: move vfs_fstatat out of line
This allows to keep vfs_statx static in fs/stat.c to prepare for the following
changes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-26 22:55:05 -04:00
Christoph Hellwig
da9aa5d96b fs: remove vfs_statx_fd
vfs_statx_fd is only used to implement vfs_fstat.  Remove vfs_statx_fd
and just implement vfs_fstat directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-26 22:55:05 -04:00
Linus Torvalds
96ed320d52 Merge tag 'vfs-5.8-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull DAX updates part one from Darrick Wong:
 "After many years of LKML-wrangling about how to enable programs to
  query and influence the file data access mode (DAX) when a filesystem
  resides on storage devices such as persistent memory, Ira Weiny has
  emerged with a proposed set of standard behaviors that has not been
  shot down by anyone! We're more or less standardizing on the current
  XFS behavior and adapting ext4 to do the same.

  This is the first of a handful pull requests that will make ext4 and
  XFS present a consistent interface for user programs that care about
  DAX. We add a statx attribute that programs can check to see if DAX is
  enabled on a particular file. Then, we update the DAX documentation to
  spell out the user-visible behaviors that filesystems will guarantee
  (until the next storage industry shakeup). The on-disk inode flag has
  been in XFS for a few years now.

  Summary:

   - Clean up io_is_direct.

   - Add a new statx flag to indicate when file data access is being
     done via DAX (as opposed to the page cache).

   - Update the documentation for how system administrators and
     application programmers can take advantage of the (still
     experimental DAX) feature"

Link: https://lore.kernel.org/lkml/20200505002016.1085071-1-ira.weiny@intel.com/

* tag 'vfs-5.8-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  Documentation/dax: Update Usage section
  fs/stat: Define DAX statx attribute
  fs: Remove unneeded IS_DAX() check in io_is_direct()
2020-06-02 19:45:12 -07:00
Linus Torvalds
1ee08de1e2 Merge tag 'for-5.8/io_uring-2020-06-01' of git://git.kernel.dk/linux-block
Pull io_uring updates from Jens Axboe:
 "A relatively quiet round, mostly just fixes and code improvements. In
particular:

   - Make statx just use the generic statx handler, instead of open
     coding it. We don't need that anymore, as we always call it async
     safe (Bijan)

   - Enable closing of the ring itself. Also fixes O_PATH closure (me)

   - Properly name completion members (me)

   - Batch reap of dead file registrations (me)

   - Allow IORING_OP_POLL with double waitqueues (me)

   - Add tee(2) support (Pavel)

   - Remove double off read (Pavel)

   - Fix overflow cancellations (Pavel)

   - Improve CQ timeouts (Pavel)

   - Async defer drain fixes (Pavel)

   - Add support for enabling/disabling notifications on a registered
     eventfd (Stefano)

   - Remove dead state parameter (Xiaoguang)

   - Disable SQPOLL submit on dying ctx (Xiaoguang)

   - Various code cleanups"

* tag 'for-5.8/io_uring-2020-06-01' of git://git.kernel.dk/linux-block: (29 commits)
  io_uring: fix overflowed reqs cancellation
  io_uring: off timeouts based only on completions
  io_uring: move timeouts flushing to a helper
  statx: hide interfaces no longer used by io_uring
  io_uring: call statx directly
  statx: allow system call to be invoked from io_uring
  io_uring: add io_statx structure
  io_uring: get rid of manual punting in io_close
  io_uring: separate DRAIN flushing into a cold path
  io_uring: don't re-read sqe->off in timeout_prep()
  io_uring: simplify io_timeout locking
  io_uring: fix flush req->refs underflow
  io_uring: don't submit sqes when ctx->refs is dying
  io_uring: async task poll trigger cleanup
  io_uring: add tee(2) support
  splice: export do_tee()
  io_uring: don't repeat valid flag list
  io_uring: rename io_file_put()
  io_uring: remove req->needs_fixed_files
  io_uring: cleanup io_poll_remove_one() logic
  ...
2020-06-02 15:42:50 -07:00
Bijan Mottahedeh
6f88cc176a statx: hide interfaces no longer used by io_uring
The io_uring interfaces have been replaced by do_statx() and are no
longer needed.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-26 16:48:06 -06:00
Bijan Mottahedeh
0018784fc8 statx: allow system call to be invoked from io_uring
This is a prepatory patch to allow io_uring to invoke statx directly.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-26 16:48:06 -06:00
Miklos Szeredi
80340fe360 statx: add mount_root
Determining whether a path or file descriptor refers to a mountpoint (or
more precisely a mount root) is not trivial using current tools.

Add a flag to statx that indicates whether the path or fd refers to the
root of a mount or not.

Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Reported-by: Lennart Poettering <mzxreary@0pointer.de>
Reported-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-14 16:44:24 +02:00
Miklos Szeredi
fa2fcf4f1d statx: add mount ID
Systemd is hacking around to get it and it's trivial to add to statx, so...

Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-14 16:44:24 +02:00
Miklos Szeredi
761e28fa27 statx: don't clear STATX_ATIME on SB_RDONLY
IS_NOATIME(inode) is defined as __IS_FLG(inode, SB_RDONLY|SB_NOATIME), so
generic_fillattr() will clear STATX_ATIME from the result_mask if the super
block is marked read only.

This was probably not the intention, so fix to only clear STATX_ATIME if
the fs doesn't support atime at all.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-14 16:44:24 +02:00
Miklos Szeredi
581701b7ef uapi: deprecate STATX_ALL
Constants of the *_ALL type can be actively harmful due to the fact that
developers will usually fail to consider the possible effects of future
changes to the definition.

Deprecate STATX_ALL in the uapi, while no damage has been done yet.

We could keep something like this around in the kernel, but there's
actually no point, since all filesystems should be explicitly checking
flags that they support and not rely on the VFS masking unknown ones out: a
flag could be known to the VFS, yet not known to the filesystem.

Cc: David Howells <dhowells@redhat.com>
Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-14 16:44:24 +02:00
Ira Weiny
712b2698e4 fs/stat: Define DAX statx attribute
In order for users to determine if a file is currently operating in DAX
state (effective DAX).  Define a statx attribute value and set that
attribute if the effective DAX flag is set.

To go along with this we propose the following addition to the statx man
page:

STATX_ATTR_DAX

	The file is in the DAX (cpu direct access) state.  DAX state
	attempts to minimize software cache effects for both I/O and
	memory mappings of this file.  It requires a file system which
	has been configured to support DAX.

	DAX generally assumes all accesses are via cpu load / store
	instructions which can minimize overhead for small accesses, but
	may adversely affect cpu utilization for large transfers.

	File I/O is done directly to/from user-space buffers and memory
	mapped I/O may be performed with direct memory mappings that
	bypass kernel page cache.

	While the DAX property tends to result in data being transferred
	synchronously, it does not give the same guarantees of O_SYNC
	where data and the necessary metadata are transferred together.

	A DAX file may support being mapped with the MAP_SYNC flag,
	which enables a program to use CPU cache flush instructions to
	persist CPU store operations without an explicit fsync(2).  See
	mmap(2) for more information.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-05-04 08:49:39 -07:00
Jens Axboe
3934e36f60 fs: make two stat prep helpers available
To implement an async stat, we need to provide the flags mapping and
the statx user copy. Make them available internally, through
fs/internal.h.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-20 17:03:54 -07:00
Christoph Hellwig
801e523796 fs: move generic stat response attr handling to vfs_getattr_nosec
generic_fillattr is an optional helper that isn't used by all file
systems, move handling purely based on inode flags to vfs_getattr_nosec,
which is common code.

This fixes setting this flag for file systems not using generic_fillattr
like xfs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-01 01:55:45 -05:00
Arnd Bergmann
82b355d161 y2038: Remove newstat family from default syscall set
We have four generations of stat() syscalls:
- the oldstat syscalls that are only used on the older architectures
- the newstat family that is used on all 64-bit architectures but
  lacked support for large files on 32-bit architectures.
- the stat64 family that is used mostly on 32-bit architectures to
  replace newstat
- statx() to replace all of the above, adding 64-bit timestamps among
  other things.

We already compile stat64 only on those architectures that need it,
but newstat is always built, including on those that don't reference
it. This adds a new __ARCH_WANT_NEW_STAT symbol along the lines of
__ARCH_WANT_OLD_STAT and __ARCH_WANT_STAT64 to control compilation of
newstat. All architectures that need it use an explict define, the
others now get a little bit smaller, and future architecture (including
64-bit targets) won't ever see it.

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-08-29 15:42:20 +02:00
Dominik Brodowski
2dae024806 fs: add do_readlinkat() helper; remove internal call to sys_readlinkat()
Using the do_readlinkat() helper removes an in-kernel call to the
sys_readlinkat() syscall.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:15:34 +02:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Jan Kara
f4a8116a4c fs: Provide __inode_get_bytes()
Provide helper __inode_get_bytes() which assumes i_lock is already
acquired. Quota code will need this to be able to use i_lock to protect
consistency of quota accounting information and inode usage.

Signed-off-by: Jan Kara <jack@suse.cz>
2017-08-17 22:06:03 +02:00
Al Viro
eb315d2ae6 ufs: restore maintaining ->i_blocks
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 16:28:01 -04:00
Linus Torvalds
204f144c9f Merge branch 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fs/compat.c cleanups from Al Viro:
 "More moving of compat syscalls from fs/compat.c to fs/*.c where the
  native counterparts live.

  And death to compat_sys_getdents64() - the only architecture that used
  to need it was ia64, and _that_ has lost biarch support quite a few
  years ago"

* 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs/compat.c: trim unused includes
  move compat_rw_copy_check_uvector() over to fs/read_write.c
  fhandle: move compat syscalls from compat.c
  open: move compat syscalls from compat.c
  stat: move compat syscalls from compat.c
  fcntl: move compat syscalls from compat.c
  readdir: move compat syscalls from compat.c
  statfs: move compat syscalls from compat.c
  utimes: move compat syscalls from compat.c
  move compat select-related syscalls to fs/select.c
  Remove compat_sys_getdents64()
2017-05-02 11:54:26 -07:00